Blade sharpener



Feb. 6, 1940. w. A. RUSSELL BLADE SHARPENER File d Jan. 21, 1937 denotesthefront of the case and 6 its back,,said

' ing' in which Patented Feb. 6, 1940 UNITED STATES PATENT cr ticsWilson A. Russell, Hartford, Conn. Application January 21, 1937, SerialNo. 121,458

3 Claims.

My invention relates to the class of devices that are employed forsharpening knives, scissors, and other blades requiring a cutting edge,and an object of my invention, among others, is the production of asharpener for this purpose that shall be simple in construction andparticularly eflicient in operation.

One form of a sharpener embodying my invention and in the constructionand use of which the objects herein set out, as well as others, may beattained is illustrated in the accompanying draw- Figure 1 is aperspective-isometric view of my improved sharpener.

Figure 2 is a front view of the same partially broken out. I

Figure 3 is a View in cross section on a plane denoted by the dottedline 3-3 of Fig. 2.

Figure-4 is a view on enlargedscale in vertical cross'section'on a planedenoted by the dotted line4 -4 of, Fig. 2.

My improved sharpener is designed for use in sharpening variousarticles, as scissors and knives, and it is my purpose to so constructit that difierent portions of the sharpening member may be used and tosuch extent that the entire cutting surface of such member may beemployed until said cutting surface is exhausted. The device is of verysimple construction comprising a case formed of a single piece of sheetmetal in proper form to enclose the sharpening element and also guidesfor the blades to be sharpened.

In the accompanying drawing the numeral 5 case comprising a single pieceof sheet metal bent into U-shape, the bent U-shaped. portion comprisingthe bottom 7 of the case- The back is bent forwardly at itsopposite sideedges to provide ends 8 which are bent to overlap the front as at E2 toa slight extent, and the front is bent backwardly at its opposite ends,as at H), to underlap the ends 8, as shown in Fig. 3 of the drawing.This provides an extremely rigidstructure to nicely fit the sharpeningelement to be hereinafter described. The case is thus formed with aclosed end and bottom and with a back and front wall, which, whilecomposed of sheet metal, yet are sufiiciently rigid for all purposesofthe sharpener. The top edges of both the front and back walls areextended upwardly and outwardly in divergent directions to form rests orsupports H for an article, as a knife I2, to be sharpened. Guides l3 areprojected'downwardly from the upper edges of the rests or supports II,and preferably at one end thereof. These parts [3 are spring guides, andthey are formed'of a separate piece of metal from the supports ll, saidsupports being comparatively rigid in order to keep a constant correctangle. These guides may be secured in any suitable manner as by weldingor otherwise. These guides are cut out preferably at opposite ends toprovide spring guides 64 which actto pressthe upper or back edge of aknife against the rests or supports H, the lower edges of the guides l3pressing the opposite edge of the knife into contactwith such rests orsupports. A sharpening member i5 is located in the case, projecting atits upper edge slightly above the case. This sharpening member may be ofany desired construction, as a matter of fact it being my intent that itshall be a fine file which may be readily purchased in the market,andwhich will therefore be hereinafter referred to as a file, with,however, no intention of limiting it to such. Bends I 6, quite sharp,are. formed at the lower edges of the rests or supports II, as shown inFigs. 1 and 4 of the drawing, and grooves l! are located below thesebends. The bends are located in contact with the file but not to exert amaterial pressure against it. I I I The extremecutting edge of a knifeblade is ground so that the opposite sides form an acute angle and it isessential in sharpening the blade that the angles of the supports i!shall be maintained to a maximum extentand to this end the front andback 5 and 6 are extended across the end of the case one being claspedabout the opposite wall to rigidly hold the front and back so that therests or supports H projecting from the upper edges of said parts willnot be sprung outwardly but will retain their positions so that theangles above referred to will not be materially changed. 7

Owing to the acuteness of the angles at the sharpened edge of the bladethe latter when placed on the guide and moved into contact with the fileat the apex of the angle has a tendency to force itself into the apex ofthe angle and downwardly between the file and the case. In order tomaintain the rests H in position without materially changing this anglethe bends It are provided as'above noted together with the grooves l1between the bends. While the bends l6 normally touch the file With alight pressure, as the blade enters the angle between a rest and thefile the bends will be forced slightly away from the file and in thisposition the bend is so curved as to recede from the blade at a pointjust removed from theextreme edge so that such edge will not come incontact with the metal of the rest but will contact only with thefile.This location of the curved surface of the bead opposite the fiatsurface of the file presents a line contact of the blade against thebead, thereby reducing the friction of the blade against the fiatsurface of the file to a minimum and also decreases the tendency of theblade to wedge between the rest and the file and therefore permits theblade to be moved with comparative ease. The lower bend I6 10- calizesthe line of bending action at this place as,

owing to the greater leverage on the rests or supports down to thisline, any bending action will take place thereat and any slight bendingaction occasioned will change the angle between the rest or support andthe file to a minimum extent and such as to be immaterial. The filingsresulting from the sharpening operation will pass into the groove l1and. will therefore not collect in the angle between the rest and theblade. This reduction in the wedging action of the blade prevents thethin extreme edge of the blade from curling away from the file by asubstantial elimination of pressure of the blade upon the file.

At a point downwardly from the top edge of the case the back wall is cutthrough forming an Opening, and a scissors blade rest l8 projectsoutwardly from the edge of this opening and at such an angle as topresent the edge of a scissors blade to the file to have the properangle formed thereon in the sharpening operation. The edge of saidopening is bent outwardly as at 24 to create a flaring mouth to receivethe scissors blade and thereby form a guide for the entry of said blade25 into the opening adjacent the rest I8 as shown in Fig. 4 of thedrawing, the rest and the guide cooperating to present the scissorsblade to the sharpening element in proper position for sharpening.

A bolt [9 extends through slots in the front and back wall of the caseunder the file so that it may be raised or lowered for a purpose to behereinafter described, a thumb nut 20 being applied to the bolt at thefront of the case.

A handle 2|, preferably made of sheet metal bent to shape, is formedwith a base 22 having tangs 23 projecting through holes in both walls ofthe case, said tangs being riveted on the projecting ends to secure thehandle in place. It is obvious that rivets may be employed in place oftangs, if desired. The two upper tangs are located on a line with thebolt IS in its lowermost position so that the file IS in its lowestposition will rest upon the tangs and upon the bolt. The upper edge ofthe file will preferably be located slightly above the bends i6 and whenthis portion of the file has been unduly worn in the sharpeningoperations the file may be moved upwardly by loosening the thumb nut 20and raising the bolt in the slots hereinbefore mentioned. This willbring a new sharpening surface into position for use. The bolt alsoserves to clamp the front and back walls of the case against the fileand hold it firmly in place.

As a matter of fact in the device which I have used for demonstrationpurposes I have employed a file one inch in width, the first and fourthquarter inches from one edge being used to sharpen knives and the secondand third quarter inches being for the purpose of sharpening scissors.One-eighth inch of each quarter inch section will first be used untilworn out and the second one-eighth inch of said sections will then beemployed. When said first one-eighth inch is worn out the thumb nut 20may be loosened and the bolt I9 raised to bring the second oneeighthinch of the section into play. When the whole sharpening surface for theknives at one edge is unduly worn the blade may be turned edge-for-edgethus bringing the sharpening surfaces at the opposite edge of the fileinto use as just described. When the entire sharpening surfaces of thesecond and third sections for the scissors blades on one side of thesharpening element are worn out by raising the blade and by reversing itedge-for-edge as hereinabove described, then the blade may be turnedfrom front to back to provide an equal amount of sharpening surface asthat worn out and which may be utilized in the same manner, it beingnoted that scissors blades are operated upon by one side of thesharpening element only at each sharpening operation, whereas with theknives only onehalf of the work by the sharpening element is requiredfor each sharpening operation, as in each operation two sides of thesharpening element are employed.

In the particular means shown herein for securing the guides I3 in placethe upper ends of the supports H are curved to form guide supports 26and the upper ends of the guides are curved to fit said supports and arelaterally extended to form wings 21. These wings have slots 23 extendinginwardly from opposite ends, and tongues 29 are bent downwardly from theends of openings 3!) in the guide slots 26. These tongues extend throughthe slots 28 and along the under sides of the curved upper ends of theguides i3, thereby retaining the guides in place. These securing meansmay be reinforced by spot welding or other similar means as desired.

I claim:

1. A sharpener including a case comprismg a support extending upwardlyand outwardly from the upper edge of said case, a guide pro- J'ectingdownwardly from the upper edge of said support and forming in connectiontherewith an opening to receive a blade while being sharpened, a springtongue located between said support and guide for pressing a bladetoward said support within said opening, and a file projecting upwardlyout of the upper edge of said case in cooperative relation with respectto said support.

2. A sharpener including a case comprising a support projecting at anangle from the upper edge of said case, a guide projecting downwardlyfrom said support to form an opening to receive a blade while beingsharpened and to contact with a blade and press it toward said support,a spring tongue projecting inwardly between said support and guide andcomposed of metal bent from within an opening created to form saidtongue and a sharpening element projecting from the upper edge of saidcase in angular relation with respect to said guide.

3. A sharpener including a case of box-like shape having an open top, asharpening member fitting said case and projecting from said open topand having a flat sharpening side surface, and a blade supportprojecting upwardly from the upper edge of one side of the case at anangle thereto and creating an acute angle between said support and thesharpening surface of the sharpening member, the bend creating saidangle being rounded in cross section to provide a line contact betweenthe blade support and sharpening member and extending lengthwise acrossthe case and an outwardly directed arched portion at the lower edge ofthe blade support parallel with said bend with the upper edge of thearched portion directed toward and merging into the bend at thesharpening line to prevent contact of the extreme sharpened edge of theblade with the case or support and provide a groove at the lower side ofsaid bend to receive filings from the cutting operation.

WILSON A. RUSSELL.

